1. Field of the Invention
The present invention relates to the production of .beta.-hydroxyesters or .beta.-hydroxyaldehydes from ethylene oxide and synthesis gas.
2. Discussion of the Background
The hydroformylation of ethylene oxide over cobalt catalysts has been known for some time to yield .beta.-hydroxyaldehydes (see, e.g., "Organic Syntheses Via Metal Carbonyls," I. Wender and P. Pino (1968), John Wiley and Sons, Inc., pp 384-388; "Carbon Monoxide in Organic Synthesis;" J. Falbe, (1970), Springer-Berlag, pp 58-59). A major problem with this reaction, however, is that it only provides low yields of aldehydes. Attempting to increase yield of aldehydes using more forcing reaction conditions or longer reaction times produces aldol condensation products instead of the desired aldehyde products.
Rhodium is not known to catalyze the hydroformylation of ethylene oxide. It is known that rhodium promotes the carbonylation of ethylene oxide to produce .beta.-lactones (see "Homogeneous Catalysis with Compounds of Rhodium and Iridium," by R. S. Dickson; D. Reidel Publishing House, 1985).
It is also known to promote the carbonylative ring opening of ethylene oxide in the presence of alcohols to yield .beta.-hydroxypropionate esters as disclosed, for example, by Kawabata et al in Nippon Kagaku Kaishi, 635 (1979). These authors disclose the use of dicobalt octacarbonyl/pyridine catalysts. The resulting products, at present, have limited utility, being used for the preparation of acrylate esters which in turn can be used for the preparation of acrylate resins and polyesters.
There is thus a distinct need for a process for readily producing useful products from ethylene oxide.